低Ni-Cr鋳鉄の二，三の性質について

Abstract

Brittleness is sometimes seen in the tray of the heating furnace made of low Ni-Cr cast irons during operation. In connection with the above phenomenon, the thermal expansion, growth, resistance to oxidation and microstructure which are the basic properties of low Ni-Cr cast irons have been studied. The results obtained are as follows: (1) Plain cast iron which contains neither Ni nor Cr is most inferior in thermal expansion, growth and resistance to oxidation, respectively. (2) The thermal expansion becomes considerably smaller as the Cr content increases. On the contrary, the thermal expansion increases with increasing Ni content. (3) The growth rate becomes clearly lower, as the Cr content increases. (4) Resistance to oxidation is improved, as the Cr content increases. And when the Ni content is low, the resistance to oxidation is good.